全文获取类型
收费全文 | 76448篇 |
免费 | 5685篇 |
国内免费 | 390篇 |
专业分类
耳鼻咽喉 | 754篇 |
儿科学 | 1827篇 |
妇产科学 | 1724篇 |
基础医学 | 9658篇 |
口腔科学 | 1944篇 |
临床医学 | 7671篇 |
内科学 | 17563篇 |
皮肤病学 | 1003篇 |
神经病学 | 6173篇 |
特种医学 | 2288篇 |
外国民族医学 | 2篇 |
外科学 | 11768篇 |
综合类 | 1140篇 |
现状与发展 | 1篇 |
一般理论 | 116篇 |
预防医学 | 6427篇 |
眼科学 | 2092篇 |
药学 | 5301篇 |
中国医学 | 152篇 |
肿瘤学 | 4919篇 |
出版年
2023年 | 372篇 |
2022年 | 583篇 |
2021年 | 1614篇 |
2020年 | 935篇 |
2019年 | 1382篇 |
2018年 | 1629篇 |
2017年 | 1130篇 |
2016年 | 1269篇 |
2015年 | 1487篇 |
2014年 | 2255篇 |
2013年 | 3439篇 |
2012年 | 4757篇 |
2011年 | 5083篇 |
2010年 | 2900篇 |
2009年 | 2710篇 |
2008年 | 4835篇 |
2007年 | 5086篇 |
2006年 | 4853篇 |
2005年 | 5018篇 |
2004年 | 4675篇 |
2003年 | 4164篇 |
2002年 | 4069篇 |
2001年 | 861篇 |
2000年 | 727篇 |
1999年 | 847篇 |
1998年 | 896篇 |
1997年 | 723篇 |
1996年 | 590篇 |
1995年 | 587篇 |
1994年 | 541篇 |
1993年 | 508篇 |
1992年 | 585篇 |
1991年 | 553篇 |
1990年 | 472篇 |
1989年 | 491篇 |
1988年 | 451篇 |
1987年 | 431篇 |
1986年 | 413篇 |
1985年 | 466篇 |
1984年 | 487篇 |
1983年 | 447篇 |
1982年 | 584篇 |
1981年 | 477篇 |
1980年 | 514篇 |
1979年 | 341篇 |
1978年 | 334篇 |
1977年 | 351篇 |
1976年 | 285篇 |
1975年 | 299篇 |
1974年 | 260篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Objective
The aim of the study was to estimate the effect of the state-based reinsurance programs through the section 1332 State Innovation Waivers on health insurance marketplace premiums and insurer participation.Data Source
2015 to 2022 Robert Wood Johnson Foundation Health Insurance Exchange Compare Datasets.Study Design
An event study difference-in-differences (DD) model separately for each year of implementation and a synthetic control method (SCM) are used to estimate year-by-year effects following program implementation.Data Collection/Extraction Methods
Not applicable.Principal Findings
Reinsurance programs were associated with a decline in premiums in the first year of implementation by 10%–13%, 5%–19%, and 11%–17% for bronze, silver, and gold plans (p < 0.05). There is a trend of sustained declines especially for states that implemented their programs in 2019 and 2020. The SCM analyses suggest some effect heterogeneity across states but also premium declines across most states. There is no evidence that reinsurance programs affected insurer participation.Conclusion
State-based reinsurance programs have the potential to improve the affordability of health insurance coverage. However, reinsurance programs do not appear to have had an effect on insurer participation, highlighting the need for policy makers to consider complementary strategies to encourage insurer participation. 相似文献2.
Rajendrababu Sharmila Puthuran George Varghese Alia Laxmi Ananya Uduman Mohammed Sithiq Wijesinghe Hiruni Kaushalya 《International ophthalmology》2022,42(8):2609-2618
International Ophthalmology - To investigate the efficacy and safety of non-valved Aurolab aqueous drainage implant (AADI) surgery combined with phacoemulsification in eyes with refractory glaucoma... 相似文献
3.
Wojciech Szychta M.D. Ph.D. Gheorghe Cerin M.D. Ph.D. F.E.S.C. Bogdan Adrian Popa M.D. Armienti Felice M.D. Guido Lanzillo M.D. Ph.D. Marco Diena M.D. Grzegorz Opolski M.D. Ph.D. F.E.S.C. 《Echocardiography (Mount Kisco, N.Y.)》2015,32(6):1040-1043
Sinus venosus atrial septal defect (SV‐ASD) usually coexists with partial anomalous pulmonary vein connection (PAPVC). It is a difficult diagnosis in transthoracic echocardiography (TTE) due to eccentric position of defects. We present a rare case of atypical anatomical variation in PAPVC, which was never described before. Two right pulmonary veins drained into superior vena cava, which overrode SV‐ASD and interatrial septum, a third pulmonary vein into the right atrium. Complete diagnosis could not be set after TTE, nor transesophageal echocardiography, whereas angio‐CT was finally conclusive. This diagnostic approach allowed the surgical planning. 相似文献
4.
5.
6.
7.
8.
9.
10.
Lorena Martin-Morales Sara Manzano Maria Rodrigo-Faus Adrian Vicente-Barrueco Victor Lorca Gonzalo Núñez-Moreno Paloma Bragado Almudena Porras Trinidad Caldes Pilar Garre Alvaro Gutierrez-Uzquiza 《International journal of cancer. Journal international du cancer》2023,152(2):283-297
Matrix metalloproteinase-11 (MMP11) is an enzyme with proteolytic activity against matrix and nonmatrix proteins. Although most MMPs are secreted as inactive proenzymes and are later activated extracellularly, MMP11 is activated intracellularly by furin within the constitutive secretory pathway. It is a key factor in physiological tissue remodeling and its alteration may play an important role in the progression of epithelial malignancies and other diseases. TCGA colon and colorectal adenocarcinoma data showed that upregulation of MMP11 expression correlates with tumorigenesis and malignancy. Here, we provide evidence that a germline variant in the MMP11 gene (NM_005940: c.232C>T; p.(Pro78Ser)), identified by whole exome sequencing, can increase the tumorigenic properties of colorectal cancer (CRC) cells. P78S is located in the prodomain region, which is responsible for blocking MMP11's protease activity. This variant was detected in the proband and all the cancer-affected family members analyzed, while it was not detected in healthy relatives. In silico analyses predict that P78S could have an impact on the activation of the enzyme. Furthermore, our in vitro analyses show that the expression of P78S in HCT116 cells increases tumor cell invasion and proliferation. In summary, our results show that this variant could modify the structure of the MMP11 prodomain, producing a premature or uncontrolled activation of the enzyme that may contribute to an early CRC onset in these patients. The study of this gene in other CRC cases will provide further information about its role in CRC development, which might improve patient treatment in the future. 相似文献